Tube-knocker



H. G. MON KHORST. TUBE KMQGKER. APPLICATION FILED lllLY 25319.19.

1,341,277. Patented May 25,1920.

flfforney.

UNITED STATES HERMANUS GERARDUS MONKHORST, OF DELFT, NETHERLANDS.

TUBE-KNOCKER.

Specification of Letters Patent.

Patented May 25, 1920.

Application filed July 25, 1919. Serial No. 313,408.

To all whom it may concern Be it known that I, HER'MANUS GERARDUS MoNKnoRs'r, a subject of the Queen of the Netherlands, residing at Delft, Netherlands, have invented certain new and useful Improvements in Tube-Knockers, of which the following is a specification.

To avoid the formation of folds when bending an iron or a steel tube of any considerable diameter it is customary to fill the tube with dry sand and then to bend it into the desired shape either mechanically or by hand, if necessary in a hot condition. Now, in order to obtain the desired result, it is essential for the sand to fill up the tube as closely as possible and for this purpose it is necessary to hammer the filled tube during a sufficiently long time. This operation takes very much time; a (lf tube, for instance, re-

quires to be hamnlered by two men for some by the hammering operation may be carried out mechanically throughout, and with this object in view said apparatus comprises in combination with a motor which is operatively coupled with a knocker or hammer, means adapted. to hold the apparatus in engagement with the tube to be hammered, said means comprising a wheel or roller adapted to be driven by the said motor.

The annexed drawing illustrates partly in elevation, partly in sectional view a practical embodiment of my invention.

The apparatus shown comprises a casing 1, and mounted in this casing is an electric motor whose shaft carries a pinion 2. The rotary motion of the motor shaft is transmitted by suitable reducing gear to a shaft 3 projecting outside the casing 1, and keyed to this projection is a disk 4 having a crank pin 5 secured thereto. Said crank pin 5 is pivotally connected with a rod 6 which in turn is pivoted to a piston 7 having freedom of reciprocatory motion in a cylinder 8. A fork 9, one end of which is rotatably connected with the piston 7 through a pin 10, has its other end pivoted by means of a pin 11 to one arm of a lever 12 pivoted at 13, the second arm of said lever 12 freely projecting into a slot of a knocker or harmmer 14 guided by a sleeve 15.

It will be understood that rotary motion of the motor shaft causes reciprocatory motion of the knocker 14, and it has been found of a flexible cord.

that cane is a very suitable material for said lever 12 which evidently should be very elastic.

Secured to the casing 1 is an electromagnet 16 whose horse shoe core is provided at opposite ends with iron rollers 18 and 19. The shaft of roller 19 has keyed to it a gear 20 driven through a gear 21 by a gear 22 on a shaft 23, the latter also carrying a worm wheel 21 meshing with a worm 25 on the shaft 3.

The commutator of motor 1 has a lever 26 and the motor is so arranged that by a rotation of said lever through 90 in one direction or the other the direction of rotation of the motor may be reversed.

The operation of the described apparatus is as follows:

The motor and the elcctromagnet are con nectecl with an electrical network by means If new the apparatus is forced to the outer wall of an iron tube and the electric circuit of the electromagnet closed, the core 17 and the rollers 18, 19 are energized and the apparatus is held in engagement with the tube by magnetic attraction between the latter and the rollers. The rotary motion of the motor causes the hammer 141 to reciprocate as required and the roller 19 to turn, whereby the apparatus moves as a whole along the pipe which is thus subjected to the successive hammer blows;

The described arrangement, which insures a perfect result as far as the condensation of the mass of sand in the tube is concerned, has the advantageous feature that it does not damage the tube as all hammer blows hit the tube with exactly the same force and at the proper point. When hammering the tube by hand power it often occurs that the hammer hits the tube with too great a force and somewhat eccentrically, whereby depressions may be made.

It is obvious that the described embodiment may be varied in many respects without departing from the scope and the spirit of my present invention. F or instance. the lever 12 might be rigid and the required re siliency provided for in the hammer itself. Further, the electric motor might be replaced by a prime mover driven by compressed air, and the magnetic means for holding the apparatus in engagement with the tube by a spring clamping device. Therefore, I do not wish to be limited to these or to other particular embodiments, but what I claim and desire to secure by Letters Patent is:

1. In an apparatus for packing metal tubes with sand, the combination of a motor; a percussion tool coupled thereto and adapted to strike the tube to be packed; and means for holding the apparatus against said tube including a wheel or roller arranged to travel directly along the tube and connected with the motor to be driven thereby.

2. In an apparatus for packing metal tubes with sand, the combination of a motor; a percussion tool coupled thereto and adapted to strike the tube to be packed; and a traveling carriage of magnetic metal engageable immediately with said tube and connected with said motor to be propelled bodily thereby along the tube, said carriage being magnetizable by the motor whereby it is held against the tube.

8. In apparatus of the type referred to,

the combination with an electric motor, and a knocker or hammer operatively coupled thereto, of means adapted by magnetic attraction to hold the apparatus in engagement with an iron or steel tube, said means including a wheel or roller adapted to be driven by said electric motor.

4. In apparatus of the character referred to, the combination of an electric motor, a shaft driven by said motor, a motor, a crank secured to said shaft and adapted to impart reci1 )rocatory motion to one arm of said lever, a hammer coupled with the other arm of said lever, and means adapted by mag netic attraction to hold the apparatus in engagement with an iron or steel tube, said electromagnetic means including a wheel or roller adapted to be driven by said electric motor.

In testimony whereof I aflix my signature.

HERMANUS GERARDUS MONKHORS'I. 

